Apparently one in eight children has intrusive thoughts at some point (an average of three or four in every school class statistically) and it's probably more common again for adults. So not everyone by any means, but it's also not at all uncommon.
The usual recommendation is to notice them and acknowledge to yourself that they are intrusive thoughts and not "you" but just that - intrusive noise. You then choose whether to tell them to go away or practice "turning down the volume" mentally (a mindfulness technique similar to imagining making a painful memory gray-scale and then minimising it on a computer screen to make it smaller and smaller until it vanishes, and doing it every time the memory turns up.
You can imagine turning down the volume of the unwanted intrusive thoughts/ voice with an old fashioned radio knob or the volume bar on your phone every time and eventually doing so becomes habit. Some people actually have positive intrusive thoughts (say hearing the voice of a beloved dead grandparent saying positive things to them as a genuinely"external" intrusive but not unwelcome, though disconcerting, voice) which they choose to "keep " or focus on but sadly it's less common and doesn't sound like what you're currently experiencing.
You definitely also need to talk to someone and sich as your GP or a mental health team as the voices are unpleasant, and you may wish to go on the waiting list for therapy and/ or accept medication such as antidepressants.
The voices network and mental health charities with helplines are good, non judgemental resources.
No matter how unsavoury the intrusive thoughts are they don't mean you are bad, they're a mental health issue just as anxiety, depression, bipolar disorders, psychosis etc. are and no more part of your personality than a rash or wart or outbreak of a skin disorder or nits which you might have but want not to have! The important thing is to remember that they are not your thoughts and you don't need to act on them, but seek help to dampen them down so you can more easily "tune them out", "turn them down", ignore them or get rid of them.